0:00:00.000,0:00:07.000
What have you learned? Well, to flip a coin n times one for k small or equal to n.
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We ask the probability--what are the chance it comes up heads k times.
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For any coin, with the probability of heads equals to all caps P,.
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we now get the following formula: n!/(n-k)!*k!.
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These are the total number of outcomes that have this property.
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And then this one has the following probability:
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P to the k, this was the (0.8)⁹ before times (1-p) to the n-k,
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which is the remaining 3 over here in this example.
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So, this formula is the probability of what's call the binomial distribution
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and really was this is the accumulated outcome of many identical coin flips,
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and it leads us beautifully to our next lesson
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when we talk about very large experiments and the normal distribution.
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What you should have learned and understand now is you can take very large experiments
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with large numbers of coin flips and compute the probability that heads comes a certain number
0:01:13.000,9:59:59.000
of times using the formula that you should now fully and wholly understand.